Eureka Gulch  
USGS 7.5' Map: Handies Peak
Difficulty: Number: Miles: Altitude: Obstacles: Time:
Easy 1 BLM4508, CR25 3.80 10,000 to 12,320 ft. NA 1-2 hours
County: San Juan
Adopted by:      
Managed by: BLM, Tres Rios Field Office
San Juan County
29211 Highway 184, Dolores, Colorado 81323
1557 Greene St, Silverton, CO 81433
Summary: Eureka Gulch road is a short drive from the town site of Eureka up past the Sunnyside Mill foundation to the site of the Sunnyside Mine and the place where Lake Emma use to be.
Attractions: History, Mining
Natural - Closed by heavy snows.
Best Time: June - May still be snowed in
July - Best
August - Best
September - Best
October - Early snows possible
Trail Heads

Camping: There are a few dispersed campsites along Eureka Creek.
Base Camp: This area would be a good place to base camp. There are many scenic 4WD roads and ghost towns in the area.
Fall Colors: Poor - This area is high alpine.
Navigation: From Silverton, CO. head northeast on Greene Street toward East 13th Street for 0.3 miles. Turn right onto County Rd 2 and go 7.7 miles. Turn left onto Animas Forks Road and go 0.4 miles. Turn slight left onto County Rd 2 and go 446 feet. Look for a sharp left going up the mountain above the old Eureka Mill foundations. This is Eureka Gulch 4WD road.
History: In 1873 during the second rush to the Animas River area east of Baker's Park (Silverton), some individuals turned their attention to other drainages besides Cunningham and Arrastra gulches. Reuben J. McNutt and George Howard searched the high peaks on the north side of the Animas River. During the summer, they made several discoveries, which confirmed their suspicions that the peaks on the north side of the river held as much promise as those on the south side. At Lake Emma, at the head of Eureka Gulch, they found a rich gold and silver vein and claimed it as the Sunnyside. The partners then crossed north over barren ridges and found another silver formation they named the Poughkeepsie. Aware that other prospectors would begin searching the area, McNutt and Howard organized the Eureka Mining District so their claims would be officially recognized.

In 1874 prospectors traced the Sunnyside vein from Lake Emma, at the head of Eureka Gulch, for a mile northeast into Placer Gulch. McNutt and Howard had all of 1873 to examine the formation and claim what they thought was the best section, which crossed Hanson Peak and over to Placer Gulch. McNutt paid Howard for his share of the Sunnyside property and began shallow development in 1874. On the other side of Hanson Peak, prospectors staked additional segments of the vein, such as the Sunnyside Extension.

Because Eureka gulch was a gateway into the high mountains, prospectors established a camp at the mouth of the drainage. McNutt's log cabin, built in 1873, became a magnet for prospectors at Eureka Gulch. Local speculators predicted that because of the strategic location, the camp would probably evolve into a formal settlement. They quickly organized the Eureka Townsite Company and platted a townsite of the same name. The founders did little to secure businesses and residents. They were busy prospecting.

Milton M. Engleman was born in 1842 in Carrolton, Illinois, and became involved in a men's clothing business in his hometown. Engleman met Emma Thompson, who operated a millinery shop. Engleman and Emma married and shortly moved to Canon City to established a clothing outlet. Later Engleman arrived in the Animas River drainage, he settled in Eureka and sent for Emma, and they brought with them dearly needed capital. The Englemans bought a share in the Eureka Townsite Company to open a mercantile and also acquired mining property. In particular, Engleman bought a half interest in the Sunnyside from Ruben McNutt, and Emma purchased interests in the George Washington and Poughkeepsie No.2. They had little left over for development of the claims, but managed to hire several miners who began sending down ore from shallow workings. Thus the Sunnyside assumed the role of one of the Eureka district's first productive operations, although the mine remained small for years.

In 1880 Milton Engleman received news that miners had struck rich gold ore in the Sunnyside on the east shore of Lake Emma, named for his wife. It was good news, The only problem being conflict among the owners. In particular, when Engleman began development during the late 1870s, he offered interests in the property to his in-laws for capital. They squabbled over profits, control, and ownership, which poisoned the relationships between Emma, Milton, and the family. Barely in control of the Sunnyside, Engleman ordered the ore to be stockpiled instead of sold.

Engleman hired John H. Terry to build a mill at the Sunnyside Mine in 1883. Terry was fresh from milling the complex gold ores of Gilpin County. Terry built a ten-stamp mill at Lake Emma which used mercury to amalgamate with free-gold and concentration machinery to recover the material that would not amalgamate. Terry was not satisfied with the small capacity and remote location of the stamp mill at Lake Emma and asked Engleman to fund a new facility. Terry wanted to electrify the mill, and have it at a lower elevation using an aerial tramway from the mine. He began construction of the Midway Mill in 1889 at a confluence of two creeks in Eureka Gulch, around one mile west of the town. The mill featured two processes that relied on mercury to amalgamate with free gold and concentration equipment to recover the material that resisted amalgamation. A small DC hydro-power plant was installed at the mill, which provided lighting and ran the machinery. When finished in 1890, the facility performed well.

Midway Mill below the Sunnyside Mine

San Juan Historical Society

This allowed Terry to increase production at the mine. The tramway would come later after capital reserved had been bolstered. Then everything changed, Milton Engleman died. Terry saw in this an opportunity to take possession of the mine as no one in the Engleman family was willing to assume Milton's administrative duties. They sold to Terry who could devote more money to the mine. By the early 1890s, the operation featured several principal tunnels driven on the vein, a large surface plant at the lowest entry, a mill on Lake Emma, the Midway Mill in Eureka Gulch, and a herd of pack animals that fed the lower mill in an endless procession. The next large project would be a tramway.

The Silver Crash slowed Terry's progress. Even though he reinvested his profits to minimize his debt, he still had to finance some of the improvements with credit. In 1894 the vein pinched out and required Terry to pay for a costly exploration campaign. The economy continued to slow and the creditors demanded payment on Terry's debt. Terry held them at bay with a clever argument. He explained to the creditors that if they seized the property now, it would sell for a fraction of its worth given the poor economic climate and they would recover only a portion of the outstanding debt. Instead, if they waited, it was only a matter of time before Terry found a continuation of the vein. The creditors agreed, and in 1895, Terry located a rich vein. He paid off all his debts, began buying out other investors for sole ownership, and saved for the tramway. By 1896, Terry felt financially secure enough to construct the tramway from the mine to the Midway Mill. Terry also entertained the long-term goal of building a third, larger mill at Eureka and extending the tramway. The fact that the vein proved to be inconsistent, however, eroded his confidence in the financing another mill. A group of New York investors took an interest in the Sunnyside and made Terry an offer of $450,000 over time with a $100,000 advance as earnest money. Terry accepted. The investors hired mining engineer Thomas A. Rickard as manager, who ran a consulting practice. From the comfort of Denver, Rickard reviewed Terry's plans and supported the idea of a third mill in Eureka. After spending a considerable amount of capital on the new mill, overhauling the Midway Mill, and other improvements, investors were horrified when miners lost the vein again. Rickard recommended an exploration campaign, but the investors did not want to risk further loss. After a half-hearted attempt to find the vein, they allowed the property to revert to Terry, who now had $100,000 to invest. Between 1896 and 1897, his miners struck the vein and produced so much ore that Terry had to run both the Midway Mill and the old facility on Lake Emma.

In 1895, Otto Mears and other Colorado capitalists incorporated the Silverton Northern Railroad and began building a line up the Animas River from Silverton to Animas Forks. The railroad company ended up purchasing Otto Mears Animas Forks Toll Road to use as the rail bed and began construction in fall 1895. Track gangs labored between snowstorms throughout the winter until they finished the line to Howardsville by May 1896. By June the crew move camp to Eureka, where Mears stopped work due to the financial burden. By 1904 the Silverton Northern Railroad finished the line from Eureka to Animas Forks. The grade proved to be one of the most difficult in Mears' railroad system. It was so steep that an engine could haul only two full or three empty cars up at a time, and they were pushed to prevent breakaways. Despite its short length, the Silverton Northern would prove to be Mears' most profitable railroad because it served one of the richest mining areas of the San Juans.

Terry Mill at Eureka in 1899

San Juan Historical Society

In 1899 the new Terry Mill (Eureka Mill) was started and it was a technical success. The problem was the Durango Smelter was shut down and Terry had nowhere to send the concentrates for refining. Miners lost the vein again, which interrupted the flow of ore to the new mill. By 1901, Terry resolved these issues, refitted the mill at Lake Emma for custom business, and electrified the mine. From this point onward, he enjoyed continuous production and notoriety in the industry for building a model operation.

In 1911, the American Zinc Ore Separating Company installed a trial recovery process in the Sunnyside Mill at Eureka. This was the first Huff Electrostatic machines in Colorado, which immediately proved successful at recovering Zinc. The Sunnyside company enlarged the plant for commercial use with this successful recovery of a marketable metal. William Terry, John Terry's son, enlarged the Huff Electrostatic plant and consulted with James H. Hyde to install flotation in 1915. Over the course of a year, the Terrys were so impressed with flotation that they moved the machinery up to the Midway Mill and installed a larger set in the Eureka plant, increasing metals recovery even further.

Sunnyside Mine in 1917 on the shores of Lake Emma

In 1917, ASARCo made a generous offer to the Terrys, (William and Joseph who were nearing retirement) for the Sunnyside property. ASARCo bought the Sunnyside, as well as the other principal mines on the ore system to ensure long-term reserves. The mining giant also enlarged the operation. In 1917, ASARCo organized the Sunnyside Mining & Milling Company and consolidated the Sunnyside, Washington, and Gold Prince groups. They planned a new mill at Eureka capable of treating 500 tons per day and to finish driving the Terry Tunnel from the mill site to undercut the vein system at great depth.

Gold Prince Mill in 1904

A crew of 40 men was sent to dismantle the Gold Prince plant at Animas Forks and incorporate the materials and equipment into the design of the new Eureka Mill (the Sunnyside Mill) which was finished in 1918.

Sunnyside Mill at Eureka with the Terry Mill at the left

At the same time a raise was started up into the old workings from the Terry Tunnel. A portion of the surface plant caught fire in 1917, and the following year it burned to the ground. The new Sunnyside Mill was ready, but the destruction at the mine shut the operation down. The company hired a workforce of eighty to rebuild, and they made progress until the influenza epidemic, avalanches, and power blackouts stalled the effort. After more than a year, the new surface plant was ready and larger than ever. In total, the complex housed 220 workers. In 1920, the national recession hit and an abrupt drop in the prices of industrial metals forced ASARCo to suspend operations yet again.

In 1922, ASARCo revived the Sunnyside Mining & Milling Company, and reopened the Sunnyside. A fortunate 162 miners were offered jobs underground and an additional fifty-four positioned at the surface plant and two mills. They produced, and milled, an impressive 500 tons of ore per day. The Sunnyside was already the largest employer in the county, even so it enlarged the operation. The company had wisely purchased all adjoining claims in 1917 to support long-term operations. In 1922, the directors moved towards development, beginning with Ruben McNutt's old Washington. Miners started sinking the Washington Shaft and by 1923, they reached the vein, and made available an entirely new ore reserve. The company increased the workforce to 360 and hired an additional 40 miners in 1926. Eight hundred tons of ore was pulled out of the mine and passed down the tramway to the mill at Eureka. The amount of concentrates supported the Silverton Northern Railroad and constituted a huge percentage of the Durango Smelter's business. During 1926, the company reached production capacity and ensured its future by expanding the underground workings into most of the adjoining ground including the Gold Prince claims to the northeast and the old Mogul property to the northwest. Most of the ore was low in grade, but the company sustained operations for the rest of the decade.

Sunnyside Mill at Eureka in 1930 (in the background)

The Great Depression caused the Sunnyside to suspended work in 1930. In 1937, the Sunnyside company announced that it was reopening its enormous mine. A crew of 177 workers were hired to prepare the surface facilities and underground workings. By September, the mine generated so much ore that it attained the status of Colorado's largest gold producer for 1937. But, the accessible ore reserves were almost gone and extensive work would be required to continue mining. The company commissioned a deep tunnel from Eureka to undercut the entire property from the lowest elevation possible, but such a project would require years. The existing ore bodies would not last that long at the current rate of production, and were in fact gutted within two years. The Sunnyside company was unwilling to pour money into the tunnel without returns from the rest of the mine. In 1939, as soon as the ore was gone, the company laid off the workforce, suspended the deep tunnel, and permanently closed the mine.

In 1959, Marcy-Shenandoah leased the Sunnyside from ASARCo and drove the American Tunnel to strike the Sunnyside and Washington veins under Lake Emma by entering from the Gold King Tunnel at Gladstone to under cut the Sunnyside workings. They enlarged the tunnel, and renamed it the American. Before Marcy-Shenandoah made progress, it sold to the Standard Uranium Corporation, based in Moab, Utah, in 1960. Standard Uranium reorganized as Standard Metals to include the new assets and pushed ahead with the original plan. The ore was removed through the American Tunnel in Gladstone and transported by truck down the old Silverton Gladstone and Northerly Railroad tight of way which had been widened to accommodate the huge trucks. In 1970, a failed copper mine in Arizona bankrupted Standard Metals, and the Washington Mining Company assumed the American Tunnel.

Lake Emma was located directly over the underground workings of the Sunnyside Mine. The mine buildings had for years been on the shores of the small alpine lake. As luck would have it, some of the most valuable ore in the Sunnyside was located directly under Lake Emma. This ore was very rich, and the mine owners mined the area under the lake. Eventually only 90 feet separated the lake and the underground tunnels. During the winter of 1977-78, a fault appeared in the mine shafts under the lake. The fault began to leak and got a little larger, and a little more water made its way into the mine. Mines often had water issues the further down they went, Of course the location of the lake made this a situation different. The maps of the mine were consulted over and over but it was felt that the distance between the lake, and mine was safe. Towards the end of May in 1978, the leak seemed to have plugged itself, and very little water made its way into the mine from the crack.

This development seemed to indicate that the mine would not have a problem with the proximity of the lake, but a miner's wife had a dream. She dreamt that the whole of Lake Emma drained into the mine. Miners are by nature superstitious so this caused quite a stir. Eventually the miners refused to work near the fault. The managers were of course upset and had the inspectors check the fault every morning for any change. All seemed well as the last shift left on Saturday the 3rd of June, 1978.

Sunday dawned a beautiful day and everyone enjoyed their day of rest in Silverton. That evening at approx 6:50 P.M., things changed forever at the Sunnyside mine. The lake broke through into the mine. By the time it was over, the entire contents of the lake had drained into the mine. Tons of silt entered the mine destroying everything in its path. The Sheriff was summoned to the portal of the American Tunnel by a concerned citizen who indicated something was very wrong at the mine. As the Sheriff made his way up Cement Creek, he was met by a wave of water 8 to 10 feet high. The water was black and full of debris.

The Sheriff met the night watchman and stood by to witness the scene at the mouth of the tunnel. A roaring torrent of water was coming from the tunnel including timbers and equipment. After it was determined that no one had been at work in the mine, the Sheriff retreated to town to spread the bad news. The mine was closed for two years in order to repair the damage. The mine never regained its profitable status and eventually due to a poor metals market, was forced to close in January of 1985. Other companies made a try at operating the mine but all were unsuccessful. The magnificent Sunnyside closed for the last time in July of 1991.

The mine is currently being reclamated by plugging the many miles of tunnels. It is thought that the reclamation project will cost more than all of the profits the mine made in its nearly 100 years of operation.

Evans, Mark L The Silverton Railroad, Gladstone Internet.
Twitty, Eric Historic Mining Resouces of the San Juan County, Colorado United States Department of the Interior: OMB No.1024-0018, Print.
Eureka Gulch road begins off of County Road 2 near the old town site of Eureka. There are no longer any of the town buildings as they were torn down to avoid taxes. The road will start up hill after a sharp left turn and head above the old Sunnyside Mill site. The foundation is all that remains.

Sunnyside Mill foundation. Valley where Eureka was is below.

photo by:
Adam M

Once past the Sunnyside Mill you will head up Eureka Gulch passing a few gated side roads. One goes to a house on the other side of the creek that looks like it is being buried by the rocks from the hill side. Past this house will be a left turn that heads down to the creek. This is a short brushy dead end spur that takes you to two campsites along the creek with potential fishing access. There is also the remians of a mine building or tram station near the end of the road.

Road down to the ghost town of Eureka

photo by:
Adam M

Back at the main road you will continue to climb up Eureka Gulch and end up getting above timberline.

Sunnyside Mine structure. Possibly tram system related.

photo by:
Adam M

At the head of the gulch are the remains of the Sunnyside Mine. Mainly large concrete foundations are on the right side of the road before you get to where Lake Emma was. The lake drained on a Sunday when the tunnels of the mine that were below the lake gave way. Just past the lake bed the road will end.

Bowl where Lake Emma was.

photo by:
Adam M

On your way back down Eureka Gulch you will get a good view of the tram line transfer station perched on a hill side.

Tram station.

photo by:
Adam M

Data updated - March 24, 2016       4WD Road driven - August 11, 2015       Copyright - 2000-2016